roaches on my screen

have done deep scan with latest update; also used Windows Live OneCare and others. These removed[?] the worm that generates "Warning! Spyware detected on your computer". I'm left with 2 problems:
when the machine is idle, roaches start crawling on the screen
when I search for some download software, a screen pops up saying my pc is infected and wants me to download some antiviral software [I've read this is bad malware]

The screenshot above shows what it looks like. Part of it is a wallpaper that is changed upon installation, so check to see if it has been changed. The message telling you to get an antivirus is part of the wallpaper. This itself is not harmful.

Another portion of it is a program call WinFixer. I ran the Eset online scanner and it cleaned it up. It has an .exe called AXPFixer.exe

I'll try to answer all replies. After the Eset scan didn't find the problem [the bugs reappeared during the scan], SysInspector.exe was downloaded and run. I was able to identify 3 problem files: blackster.scr, BLACKSTER.SCR-2BEB033F.pf, BLACKS~1.SCR-0AE854CA.pf which were then removed from the Windows directory. In the registry, SCRNSAVE.EXE was also pointing to BLACKSTER. This was fixed using Control panel/display/screen saver.

Some postings refer to this adware as BLACKSTER - there are other names [or causes]. When the mouse moves the bugs go away. Originally, I was getting the screen shot - that was a wallpaper problem that was fixed [I don't remember how [age-disadvanteged]]. Hopefully, these symptoms will not reappear.